Porous Toner via Double Emulsion Polymerization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for producing electrostatographic toner particles, such as conventional melt-pulverized and chemically prepared toner techniques, face challenges including high manufacturing costs, particle size distribution control issues, and the need for complex multi-step processes, which lead to inefficient production of porous toner particles with controlled porosity and size.
Innovation Solution
A one-step homogenization process is developed to create a water-in-oil-in-water double emulsion, where an organic phase with solid hydrocolloid particles is dispersed in an aqueous phase, allowing for the formation of porous polymeric particles with controlled narrow particle size distribution and porosity, simplifying the manufacturing process and reducing costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional melt-pulverized method is used to produce toner particles, then manufacturing process is simple, but particle size distribution is wide and manufacturing cost is high
Solution Approach 1:
The invention changes the physical-chemical parameters of the system by using polymerizable monomers instead of pre-formed polymers, and by controlling the polymerization reaction conditions (temperature, initiator concentration, monomer ratio) to achieve narrow particle size distribution during in-situ polymerization in the emulsion droplets
Solution Approach 2:
The invention utilizes phase transition of monomers to polymers during polymerization, where the phase change from liquid monomer to solid polymer occurs within the emulsion droplets, enabling controlled particle formation with uniform size and narrow distribution
2Manufacturing precision
If chemically prepared toner (ELC) method is used to control particle size, then particle size distribution is narrow, but process complexity and manufacturing cost increase
Solution Approach 1:
The invention merges the emulsion formation step and polymerization step into a single integrated process, where polymerization occurs directly within the emulsion droplets during their formation, eliminating the need for separate polymerization and emulsion steps required in conventional ELC methods
Solution Approach 2:
The invention performs preliminary action by pre-mixing polymerizable monomers with the organic phase before emulsion formation, so that polymerization can occur in-situ within the droplets during the emulsion process, simplifying the overall工艺流程
3Quantity of substance
If porous toner particles are produced to reduce toner mass, then cost per page decreases, but control over porosity and particle size becomes difficult
Solution Approach 1:
The invention changes parameters by controlling the amount of porogen, polymerization conditions, and monomer composition to precisely control both the porosity (30-70%) and particle size (5-20 μm) of the toner particles, achieving narrow size distribution while maintaining desired porosity
Solution Approach 2:
The invention creates porous toner particles by incorporating porogen substances (salt particles, sugar particles, or gas bubbles) into the emulsion droplets during polymerization, which leave controlled void spaces after removal, achieving the desired porosity for reduced toner mass while maintaining particle size control
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method enables the production of porous toner particles with controlled porosity and size distribution, reducing the toner mass required for imaging, lowering production costs, and improving print quality and efficiency, while expanding the application areas of electrophotographic processes.
Implementation Method 1
dispersing the organic phase in an aqueous phase in the presence of a controlled amount of stabilizing agent to form an emulsion of droplets of the organic phase dispersed in the external aqueous phase
Implementation Method 2
the hydrocolloid particles in the organic phase droplets are swelled with water from the external aqueous phase to form internal droplets of an aqueous phase
Implementation Method 3
droplets of the double emulsion are polymerized to form porous polymeric particles
Implementation Method 4
The organic solvent is subsequently removed from the resulting porous particles
Data Source
AI summary
A method of manufacturing a double emulsion with narrow dispersed phase particle size distribution comprising: providing an organic phase comprising solid hydrocolloid particles dispersed in an organic solvent; and dispersing the organic phase in an aqueous phase in the presence of a controlled amount of stabilizing agent to form an emulsion of droplets of the organic phase dispersed in the external aqueous phase, wherein the hydrocolloid particles in the organic phase droplets are swelled with water from the external aqueous phase to form internal droplets of an aqueous phase in the organic phase droplets, thereby forming a double emulsion comprising droplets of the organic phase of controlled narrow particle size distribution in the external aqueous phase, where the organic phase droplets contain internal droplets of an aqueous phase. A method for producing porous polymeric particles by such a double emulsion method, wherein the organic phase further comprises a polymer resin, and wherein the organic solvent is removed from the dispersed organic phase droplets to form porous toner particles.